Quantitation of two or more drugs simultaneously will be achieved by solid-state immune technology. This utilizes high titer specific IgGs from goats and mouse cell culture. Homologous iodinated radioligands will be synthesized. Assays will accomodate interchangeably blood, serum and urine. Breath is passed through a solid system to isolate cannabinoids for quantification. Blood delta 9-THC and behavior will be compared over time in various marijuana users whose habits differ.